<!DOCTYPE html>
<html>
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <meta http-equiv="X-UA-Compatible" content="ie=edge">
  <title>rem 演示</title>
  <style type="text/css">
  html {
    font-size: 100px;
  }

  div {
    background-color: #ccc;
    margin-top: 10px;
    font-size: 0.16rem;
  }
  </style>
</head>
<body>

<p style="font-size: 0.1rem">rem 1</p>
<p style="font-size: 0.2rem">rem 1</p>
<p style="font-size: 0.3rem">rem 1</p>

<div style="width: 1rem;">
  this is div1
</div>
<div style="width: 2rem;">
  this is div2
</div>
<div style="width: 3rem;">
  this is div3
</div>

</body>
</html>
